docs: def _unpack_wide(bc, offset):
      """
      unpacker for wide ops
      """
  
      code = ord(bc[offset])
  
      if code == OP_iinc:
          return _unpack(_struct_BHh, bc, offset)
  
      elif code in (OP_iload, OP_fload, OP_aload, OP_lload, OP_dload,
                    OP_istore, OP_fstore, OP_astore, OP_lstore,
                    OP_dstore, OP_ret):
  
          return _unpack(_struct_BH, bc, offset)
  
      else:
          # no other opcodes are valid, so shouldn't have fallen through
          # to here.
          assert False